This invention relates generally to electric motors and, more particularly, to a two compartment electric motor.
Electric motors such as, for example, single phase induction motors, are manufactured in a variety of configurations for use in a number of different applications. For example, swimming pools and whirlpool spas typically use a number of electric motors for various purposes such as, for example, driving a water pump for water circulation purposes. Moisture, dust, and other contaminants, which may be prevalent in the environments associated with these types of applications, may adversely interfere with the operation of the motor and, over time, may lead to failure of the motor. To provide protection against the adverse effects posed by these contaminants, various techniques and motor designs have been utilized.
One approach to facilitate minimizing adverse effects from contaminants is to utilize a two-compartment motor. In a two-compartment motor, the stator, armature, and other primary motor components are contained in a first compartment and the secondary electrical components are contained in a second compartment. For example, U.S. Pat. No. 4,593,163 discloses a two compartment motor in which a starting capacitor, a thermal protector, a terminal board, a starting switch assembly, and a manually actuable switch are mounted to an end shield of an induction motor. A thermoplastic molded cover is secured to the motor with axially directed screws to define the second compartment of the motor.
U.S. Pat. No. 5,245,237 discloses another two-compartment motor in which a control assembly is mounted within a second compartment of a two-compartment motor. The control assembly includes a control plate, a plurality of electrical components, and mounting means for securing the electrical components in position on the control plate. To switch the voltage setting of the motor between high and low settings, a voltage selection switch is mounted on the control plate within the secondary compartment.
Constructing a two-compartment electric motor may be more costly than constructing other types of electric motors. For example, the costs of manufacturing a two-compartment motor are higher than the cost associated with manufacturing a one-compartment motor because of, for example, the inherent material costs associated with the second compartment. Second, in at least some known two-compartment motors, minimizing exposure to moisture, dust, and other contaminants is difficult because the components must be ventilated.
In one aspect, a motor including a first compartment, a second compartment, a frame, a first end shield, a second end shield, an armature shaft, a stator winding, an armature, a cover, and a switchboard is provided. The first and second end shields are disposed adjacent opposing ends of the frame to define the first compartment. The armature shaft extends between the first and second end shields. The stator winding is supported by the frame within the first compartment. The armature is rotatably supported by the end shields and disposed within the first compartment adjacent the stator winding. The cover includes a first end, a peripheral edge, and ventilation openings. The cover peripheral edge is mounted to the motor adjacent the second end shield. The ventilation openings include a plurality of openings positioned along at least part of the cover peripheral edge and in the cover first end. The switchboard is mounted to the second end shield to define the second compartment between the switchboard and the second end shield. The switchboard includes a mounting means for securing a plurality of electrical components.
In another aspect, a two compartment motor including a frame, a first end shield, a second end shield, a stator winding, an armature, a cover, and a switchboard is provided. The first end shield and the second end shield are disposed adjacent opposing ends of the frame to define a first compartment. The stator winding is supported by the frame within the first compartment. The armature is rotatably supported by the end shields within the first compartment. The cover includes a plurality of cooling openings. The cover is mounted to the motor adjacent the second end shield. The switchboard is mounted to the second end shield to define the second compartment between the switchboard and the second end shield. The switchboard includes a mounting means for securing a plurality of electrical components within the second compartment.
In another aspect, a motor including a first compartment, a second compartment, a cover, and a switchboard assembly is provided. The first compartment is defined between a first end shield and a second end shield. The cover having ventilation openings is mounted adjacent the second end shield. The switchboard assembly is mounted to the second end shield to define the second compartment.